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arXiv · 2109.09047

Model-Free Safety-Critical Control for Robotic Systems

Tamas G. Molnar·Ryan K. Cosner·Andrew W. Singletary·Wyatt Ubellacker·Aaron D. Ames
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Abstract

This paper presents a framework for the safety-critical control of robotic systems, when safety is defined on safe regions in the configuration space. To maintain safety, we synthesize a safe velocity based on control barrier function theory without relying on a -- potentially complicated -- high-fidelity dynamical model of the robot. Then, we track the safe velocity with a tracking controller. This culminates in model-free safety critical control. We prove theoretical safety guarantees for the proposed method. Finally, we demonstrate that this approach is application-agnostic. We execute an obstacle avoidance task with a Segway in high-fidelity simulation, as well as with a Drone and a Quadruped in hardware experiments.

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BibTeXRIS

Tamas G. Molnar, Ryan K. Cosner, Andrew W. Singletary, Wyatt Ubellacker, Aaron D. Ames. 2021-09-19. Model-Free Safety-Critical Control for Robotic Systems. https://doi.org/10.1109/lra.2021.3135569

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